Bracing for scaffolds and the like



1955 J. A. KIRKPATRICK BRACING FOR SCAFF'OLDS AND THE LIKE Filed Feb.13, 1951' his a r roe/V5 rs.

United States Patent BRACIN G FOR SCAFFOLDS AND THE LIKE John A.Kirkpatrick, Zelienople, Pa., assignor to Universal Manufacturing Corp.,Zelienople, Pa., a corporation of Pennsylvania Application February 13,1951, Serial No. 210,665

1 Claim. (Cl. 304-2) This invention relates to the bracing of metalscaffolds, bleachers and the like, and more particularly to the bracesand the members that detachably connect them to the legs of thestructure being braced. For the sake of illustration this invention willbe described as applied to metal scaffolds formed from spaced end panelsthat are connected by removable braces, but it is not limited thereto.

It is among the objects of this invention to provide such bracing inwhich the braces are moved horizontally into and out of position, inwhich the ends of the braces can not rotate in a vertical plane againstthe legs they are bracing, in which the braces are retained in place bygravity-actuated locking members, in which the locking members arepositive in action and limited to movement over a very short distance,and in which the supporting members for the braces are simple inconstruction an inexpensive to make and fasten to the legs.

According to this invention, horizontal pins, preferably of non-circularcross section, are rigidly connected to a pair of spaced vertical legsin such a manner as to project from the sides of the legs. Forconnecting the legs together a removable brace has end portions providedwith openings for receiving the pins. Each of these openings is ofsubstantially the same size and shape as the noncircular pins in crosssection so as to keep the brace from rotating on the pins. By preventingthe brace from rotating on the pins, the number of braces can bereduced. Thus, in a scaffold formed from end panels, only one brace needbe provided at each side of the scaffold between any given pair of endpanels. Each brace-supporting pin has a vertical slot in it at the sideof the brace opposite to the adjoining leg, and a latch is disposed inthe slot with its outer end pivotally mounted therein. The inner end ofthe latch normally projects below the pin to lock the brace thereon, butthe latch is adapted to be swung up manually into the pin slot to permitthe brace to pass outward over it. The pin is shaped to limit thedistance the latch can swing downward in the slot, and also preferablyis shaped to limit the distance the latch can be swung upward in theslot so that the movements of the pin in both directions will becontrolled. The pin preferably is formed from three bars disposed sideby side, with the center bar shorter than the other two so as to formthe latch-receiving slot.

The preferred embodiment of the invention is illustrated in theaccompanying drawings, in which Fig. 1 is a perspective view of asection of a scaffold provided with my bracing; Fig. 2 is an enlargedfragmentary view taken on the line II-II of Fig. l, to show the outerend of one of the brace-supporting pins; Fig. 3 is a reduced horizontalsection through a leg, showing the pin from above; Fig. 4 is an enlargedcombination side view and section of the pin taken on the line IV-IV ofFig. 3; and Fig. 5 is a view similar to Fig. 4, showing a modificationof this invention.

Referring to Fig. 1 of the drawings, each of a pair of verticalprefabricated scaffold end frames of any suitable construction hastubular legs 1 that may be rigidly connected by horizontal cross members2 upon which wooden planking (not shown) may be placed to form a workingplatform. When the scaffold is assembled, the end frames are heldupright by means of inclined side braces 3, and they may be furtherbraced by crossed horizontal braces 4.

In order to detachably connect the ends of the braces to the scaffoldlegs, supporting pins 6 are fastened to each leg near its upper andlower ends. As shown in Fig. 2, each pin is non-circular in crosssection, preferably being 2,701,167 Patented Feb. 1, 1955 rectangular.The legs are provided with holes of the same shape as the pins forsnugly receiving them. Each pin is inserted in a pair of holes in a legwith its opposite ends projecting therefrom, as shown in Figs. 3 and 4.The inner end of the pin projects only a short distance and is connectedby a weld 7 to the leg to anchor the pin in it. The other or outer endof the pin projects a much greater distance from the leg, most suitablyfrom the inside of the leg, which is the side nearest to the other legof the same frame. In this position the pins are more protected than ifthey projected from the outside of the The braces 3 and 4 that areconnected to the pins may be formed from members of any desired shapeand cross section, but their ends should be provided with openings ofsubstantially the same size and shape as the pins 6 in cross section.Each of the braces shown in the drawings happens to be formed from alength of pipe provided at its ends with vertical slots in which shortmetal plates 9 are welded. Each of these plates is provided with arectangular opening 10 for more or less snugly receiving one of therectangular pins. That is, the ends of the braces can he slid inwardover the pins. This type of connection prevents the brace from rotatingaround the pins and thereby makes it feasible to use only one brace 3 ateach side of the scaffold between each pair of panels. Of course, two ormore braces can be used if desired. The pins project far enough from thelegs to accommodate at least three braces per pin.

The long projecting portion of each pin 6 is provided with a verticalslot 12 that extends entirely through it from top to bottom and from itsouter end inward toward the adjoining leg. It is preferred to form theslot by making the pin from three fiat bars 13, 14 and 15 of suchthickness that when disposed side by side their combined cross sectionalarea will be square. The intermediate or filler bar 14 is shorter thanthe outside bars and is spaced from their outer ends to form slot 12between their outer end portions. The three bars are held together bythe surrounding leg and by weld 7.

Loosely disposed in slot 12 is a latch 17, the outer end of which ispivotally mounted on a rivet 18 extending across the outer end of theslot with its heads countersunk in the opopsite sides of the pin so thatthe rivet will not project beyond the surface of the pin. At no point isthe vertical dimension of the latch greater than the height of the slot.It will be seen that with this construction the inner end of the latchnormally will swing down by gravity. It is spaced from the leg farenough to permit the ends of braces to be located between the latch andleg.

To limit the distance that the latch can project below the pin, theinner end of the pin slot is positioned to be engaged by a portion ofthe inner end of the latch after it has swung downward a predeterminedamount. Preferably, this is accomplished by providing the inner end ofthe latch and the inner end of the slot with cooperating projectionsthat will engage each other when the latch has swung downward thedesired distance and stop further movement of the latch. Most suitably,the end of filler bar 14 at the inner end of the slot has a recess 19 init extending toward the adjoining leg, and the inner end of the latchhas a projection or point 21 that projects loosely into the recess andnormally is supported by its lower wall. The same latch point willengage the upper wall of the recess, when the latch is swung manuallyupward in the slot to the broken line position shown in Fig. 4, beforethe latch can project from the top of the slot and interfere withsliding the braces outward along the pin. Consequently, the cooperatingpoint and recess lock the latch in the pin slot by limiting verticalswinging of the latch in both directions. Latch point 21 preferably isformed by providing the inner end of the latch with a two-sided notchwhich receives the portion of the pin below its recess. The side 22 ofthis notch that normally extends below the pin is vertical and forms anabutment that holds the braces on the pin. The lower surface 23 of thelatch is inclined from the lower end of this vertical side outwardandbugward into the pin for a purpose about to be descri e When theopening in the end of a brace is lined up with one of the pins 6 andthen the brace is pushed inward along the pin, the lower inclinedsurface 23 of the latch is engaged by the bottom of the brace openingand is forced upward, thereby swinging the latch up into the pin. Assoon as the end of the brace passes the lower inner corner of the latch,the latch will swing down again by gravity and the downwardly projectingportion, bounded by surfaces 22 and 23, will form a lock that will holdthe brace on the pin. The vertical locking surface 22 usually is spacedfar enough from the leg to permit at least three braces to be locked onthe pin. Any movement of the braces outward along the pin and againstthe locking surface of the latch will tend to swing the latch downward,whereby the latch will positively lock the braces on the pin. When it isdesired to remove the braces from the pins, the inner end of the latchis raised manually to the broken line position of Fig. 4 so that thebraces can be pulled out along the latch and off the end of the pin.

t will be seen that in this bracing the braces are held on the pins bylatches that automatically swing down by gravity into locking positionas soon as the braces are slid inward over them. The braces then can notbe removed from the pins until the latches have been swung upward byhand into the pin slots. This locking mechanism is of simpleconstruction and there is nothing about it to get out of order or tocause it to fail to operate automatically. Each latch is locked in thesupporting pin by means of the recess 19 which receives the inner point21 of the latch. The latch therefore must always be either entirelywithin the slot or project a limited distance below it. The pin slot andthe latch-retaining recess are easily formed by making the pin fromthree bars placed side by side, the middle bar having previously beennotched at one end to form the recess. No vertical movement of thebraces is required in order to mount them on the pins or to remove themtherefrom. Consequently, if desired, the pins can be located close tothe overlying horizontal cross members 2 of the end panels. A majoradvantage of this bracing is that it prevents relative rotation ortilting between the braces and legs in a vertical plane.

In the modification shown in Fig. 5, the pin again is formed from twoside bars 25 and 26 spaced apart by a filler bar 27, but all three barsare shorter than those forming pin 6, because the inner end of themodified pin is welded directly to the leg 28 without extending throughit. The weld is shown at 24 in the drawings. The latch 29 is shown inits uppermost position, where it is being held by the thumb 30 of aworkman. This particular pin is only long enough to support two braces,but of course it could be made longer if desired.

According to the provisions of the patent statutes, I have explained theprinciple of my invention and have illustrated and described what I nowconsider to represent its best embodiment. However, I desire to have itunderstood that, within the scope of the appended claim, the inventionmay be practiced otherwise than as specifically illustrated anddescribed.

I claim:

The combination with a pair of spaced vertical legs, of bracingcomprising pins of rectangular cross section projecting from the sidesof the legs, a removable brace for connecting the legs together andhaving end portions provided with rectangular openings therethrough forreceiving said pins, each pin being formed from a pair of side barsspaced apart by an intermediate bar, the intermediate bar terminatingbetween the adjoining leg and the outer ends of the side bars to form avertical slot through the pin between the outer portions of the sidebars, a latch disposed in the slot, and a pivot connecting the outer endof the latch to the outer ends of said side bars, the inner end of thelatch normally projecting below the pin to lock the brace thereon, thelatch being adapted to be swung up manually into the slot to permit thebrace to pass outward over it, and said intermediate bar being providedat the inner end of said slot with a recess extending toward theadjoining leg, and the inner end of the latch having a portionprojecting loosely into said recess to limit the distance the latch canswing downward in the s ot.

References Cited in the file of this patent UNITED STATES PATENTS233,281 Reinhold et a1. Oct. 12, 1880 336,100 Ferry Feb. 16, 18861,733,333 Coplan Oct. 29, 1929 1,950,290 Benson Mar. 6, 1934 2,099,116Kalmbach Nov. 16, 1937 2,183,679 Hillis Dec. 19, 1939 2,435,171 WeiszJan. 27, 1948 FOREIGN PATENTS 12,612 Great Britain of 1906 251,754 GreatBritain May 13, 1926

